U.S. Pat. No. 5,700,474 issued on Dec. 23, 1997 to Marvin F. Preiser and Peter F. Vogt teaches the use of liquid bird aversion solutions including solutions having methyl anthranilate. Incorporated herein by this reference, '474 teaches solutions (referred to collectively as “the solution”) for spraying onto the surface of fruits, berries, and water, etc. to neutralize the natural attraction birds have for such agricultural assets. The solution is sprayed onto the assets for protection and forms a thin film. When the birds ingest the assets, the flavor is repugnant to them.
While safe for humans, the chemistry of the solution taught in '474 breaks down to anthranilic acid, which is a corrosive chemical that causes phytotoxicity on the leaves of sprayed plants. Attempts to save the plants by encapsulating the sprayed solution in clay only delays the breakdown. The drawbacks to current bird aversion solutions include that aversion only occurs upon ingestion meanwhile, all sprayed plants suffer from phytotoxicity.
Thus, rather than wait for birds to ingest the solution, the present invention provides an airborne broadcast of the solution that repels birds without coming in direct contact with plants. A fogging machine broadcasts the solution by vaporizing its oil-based carrier with intense heat. The vapor shoots out of the exhaust tube with a noise similar to that of a lawn mower. While airborne, the droplets are inhaled by birds and cause the birds to associate the irritation and smell they detect with the place sprayed at in general and not with a specific agricultural asset, making the airborne fog an effective repellent in places such as barns, orchards and fields. Additionally, airborne fog has proven useful in hangers and on runways to protect aircraft.
Foggers produce a droplet size of solution that is approximately 30 microns in diameter on average. When foggers are used, the droplets settle out of the air too quickly and repeated foggings are necessary to achieve a prolonged effect. In addition, seeing the fog allows birds to associate the irritating quality of the fog with the presence of the fog, thus, enabling the birds to strategically avoid the fog rather than the place. Birds are also able to see the fog from afar and thus alerted, birds employ natural defenses to the fogged solution including holding their breath and deploying a mucous membrane in their eyes. Producing larger droplets proved too large for efficient repelling of birds.
Properties of the fogger also prevent entirely efficient use of the solution. The heat produced by the fogging degrades the solution. Even though some fogger settings produce at least some droplets under 10 microns, the greater portion, sometimes as much as 90%, are large droplets with their inherent shortcomings as described above.
Thus, there currently exists an unmet need in the art for a method of dispersing bird aversion solutions without the use of degrading heat to routinely produce a droplet of less than ten microns in diameter.